move pi-mono into companion-cloud as apps/companion-os

- Copy all pi-mono source into apps/companion-os/
- Update Dockerfile to COPY pre-built binary instead of downloading from GitHub Releases
- Update deploy-staging.yml to build pi from source (bun compile) before Docker build
- Add apps/companion-os/** to path triggers
- No more cross-repo dispatch needed

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/web-ui/src/components/sandbox/AttachmentsRuntimeProvider.ts

@@ -0,0 +1,70 @@
+import { ATTACHMENTS_RUNTIME_DESCRIPTION } from "../../prompts/prompts.js";
+import type { Attachment } from "../../utils/attachment-utils.js";
+import type { SandboxRuntimeProvider } from "./SandboxRuntimeProvider.js";
+
+/**
+ * Attachments Runtime Provider
+ *
+ * OPTIONAL provider that provides file access APIs to sandboxed code.
+ * Only needed when attachments are present.
+ * Attachments are read-only snapshot data - no messaging needed.
+ */
+export class AttachmentsRuntimeProvider implements SandboxRuntimeProvider {
+  constructor(private attachments: Attachment[]) {}
+
+  getData(): Record<string, any> {
+    const attachmentsData = this.attachments.map((a) => ({
+      id: a.id,
+      fileName: a.fileName,
+      mimeType: a.mimeType,
+      size: a.size,
+      content: a.content,
+      extractedText: a.extractedText,
+    }));
+
+    return { attachments: attachmentsData };
+  }
+
+  getRuntime(): (sandboxId: string) => void {
+    // This function will be stringified, so no external references!
+    // These functions read directly from window.attachments
+    // Works both online AND offline (no messaging needed!)
+    return (_sandboxId: string) => {
+      (window as any).listAttachments = () =>
+        ((window as any).attachments || []).map((a: any) => ({
+          id: a.id,
+          fileName: a.fileName,
+          mimeType: a.mimeType,
+          size: a.size,
+        }));
+
+      (window as any).readTextAttachment = (attachmentId: string) => {
+        const a = ((window as any).attachments || []).find(
+          (x: any) => x.id === attachmentId,
+        );
+        if (!a) throw new Error(`Attachment not found: ${attachmentId}`);
+        if (a.extractedText) return a.extractedText;
+        try {
+          return atob(a.content);
+        } catch {
+          throw new Error(`Failed to decode text content for: ${attachmentId}`);
+        }
+      };
+
+      (window as any).readBinaryAttachment = (attachmentId: string) => {
+        const a = ((window as any).attachments || []).find(
+          (x: any) => x.id === attachmentId,
+        );
+        if (!a) throw new Error(`Attachment not found: ${attachmentId}`);
+        const bin = atob(a.content);
+        const bytes = new Uint8Array(bin.length);
+        for (let i = 0; i < bin.length; i++) bytes[i] = bin.charCodeAt(i);
+        return bytes;
+      };
+    };
+  }
+
+  getDescription(): string {
+    return ATTACHMENTS_RUNTIME_DESCRIPTION;
+  }
+}